Valmiki Ramayana Sundara Kanda Sarga 38 Shloka 8
Original Shlokaलङ्काया दुष्प्रवेशत्वाद्दुस्तरत्वान्महोदधेः। सामर्थ्यादात्मनश्चैव मयैतत्समुदीरितम्।।5.38.8।।
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लङ्कायाः of Lanka, दुष्प्रवेशत्वात् difficult to enter, महोदधेः of the ocean, दुस्तरत्वात् difficult to cross, आत्मनः of my self, सामर्थ्याश्चैव because of my capacity, मया by me, एतत् all this, समुदीरितम् pronounced.
"Crossing the ocean and entering Lanka are difficult. But I accomplished it. Hence my proposal.